[ballen@uwm.edu] libc/2269: triginometric argument reduction error in libm

[Geoff Keating]

> Cc: ballen@uwm.edu, Stephen L Moshier <moshier@mediaone.net>
> From: Andreas Jaeger <aj@suse.de>
> Date: 20 May 2001 11:44:10 +0200

> Hi Glibc Developers,
> 
> here's a report about problems with the trigonmetric range reduction
> in glibc.
> 
> Any comments or suggestions?

Someone needs to fix libc/sysdeps/i386/fpu/s_sin.S so that it does
proper range reduction, I think.  It works fine on non-x86 chips.

Intel's manual (I was looking at the 'Pentium Processor Family
Developer's Manual, volume 3') has some spectacularly bad advice on
how to do range reduction.  I would suggest ignoring it.

-- 
- Geoffrey Keating <geoffk@geoffk.org>